This invention relates to communications systems and, more particularly to telephony conducted over packet networks.
To provide telephonic communications between computer terminals connected to a packet network, xe2x80x9cvoice over IPxe2x80x9d (VoIP) software called xe2x80x9csoftphonexe2x80x9d software is employed that typically conforms to the protocols defined in Recommendation H.323 of the International Telecommunications Union (ITU) entitled xe2x80x9cVisual Telephone Systems and Equipment for Local Area Networks which Provide a Non-guaranteed Quality of Servicexe2x80x9d. U.S. Pat. No. 5,907,604 provides for the display of a call-waiting xe2x80x9cpop-upxe2x80x9d window at the called computer terminal after an end-to-end connection has been established through the IP network to inform the called party of the caller""s name or telephone number before the call is answered. This patent is typical of prior art usage of the H.323 protocol which does not provide for wideband or multimedia transmission until an end-to-end connection is established through the network. The first above-identified related copending application improves the reliability of calling party identification by employing a feature server that obtains xe2x80x9ccaller-IDxe2x80x9d information from the telephone company rather than relying on the information provided by the caller.
In a packet switched communications system which is intended to serve business customers it is important, not only to identify the caller, but also the reason that the call is being made. This is of special importance where a number of calls may be simultaneously incoming to a called party who has operators or sales attendants who must field hundreds or thousands of calls in a day. To facilitate the handling of such calls it would be advantageous to obtain sufficient information from callers before any call is answered or end-to-end connection established between the caller and the ultimate destination so as to be able to determine the priority of calls and/or the order in which they are to be answered, or to whom a call should ultimately be directed.
In accordance with the principles of the invention, a feature server in a packet network employs a mixture of control messages common in VoIP telephony with messages that are beyond the band of the control message to enable a subscriber expecting a commercial volume of telephone traffic to create, store and exchange with callers a questionnaire or information gathering form, hereinafter xe2x80x9cIGFxe2x80x9d, designed to elicit the type of information about the calling party that the called subscriber needs to know before it is necessary to answer the call. In the preferred embodiment, when a call is made to the directory number of the subscriber, the feature server receives an H.323 Call Setup message which causes the feature server to enter the call in a call queue. An application program running on the feature server observes the change in the call queue and advantageously sends only the changed information as an IP broadcast to the subscriber""s operators"" or attendants"" VoIP terminals via a hypertext protocol (http) transmission. Since only the delta change is transmitted, and since only a single message is broadcast, the amount of data sent over the local area network (LAN) is relatively small. At the operator terminals, an application program displaying the queue accepts the change to the queue and writes that change to an array. The screen at a particular operator would be updated to show the changed information if the screen were being actively viewed by the operator. If the queue was large and the queue was being scrolled through by the agent, the data would be drawn on the screen with the current queue information. For example, the nature or purpose of the call specified by the caller in the IGF, parsed by the feature server, is used to route the call to an appropriate destination. The feature server keeps track of completed IGFs by indexing them against callers"" directory numbers, detects when a previous caller makes a repeat call, how long the call has been xe2x80x9cin queuexe2x80x9d and includes these facts in a queue display, together with telephone company supplied caller-ID information. The IGF allows a caller to indicate the urgency of his call and this information is also included in the queue display to allow an operator to reposition the call within the queue of incoming calls or to divert the call to another directory number.